Abstract: To reduce the harmful substances in cigarette, three kinds of water-soluble polymers were selected to modify the filter rods of heat-not-burn tobaccos by dipping and freeze-drying technology. The three polymers of sodium alginate（SA）, polyvinyl alcohol（PVA） and polyethylene glycol（PEG） with different contents were loaded onto the filter rods. The modification effects of the composite filters were evaluated through SEM, suction resistance, CO content, nicotine content, total particulate matter content and tar rejection rate. The results show that the filter rods modified by PEG-2 has the best comprehensive performance with little increased suction resistance. The tar content in the flue gas of PEG-2 modified filter rods is reduced by 18.3%, and the total particulate matter content is decreased by 15.62%.